The first paperclip was patented in 1867 by Samuel B. Fay. Following this in quite a few new paperclips were patented, wherein the Gem paper clip (the wire clip with three curved parts) is the best known. Where this patent refers to the “traditional paperclip”, this means the wire paperclip including all variants which are based on the same function principle. Almost all paperclips acquire their binding power by exerting with the paperclip a clamping force on the stack of sheets, whereby they are joined together. This clamping force is achieved by a combination of the stiffness of the material (metal or plastic) and the shape of the paperclip. Benefits of traditional paperclips are the low costs and intuitive function of the clips. Disadvantages of traditional paperclips are the moderate binding quality (stacks of sheets can fall out from between the stack of connected sheets of paper) and the chance of damaging the paper by the protruding ends of the wire of the paperclips. Another disadvantage of the traditional paperclip is the use of material. Paperclips are made of metal or plastic. These are not sustainable materials, whereby the paperclips have a negative effect on the well-being of the environment. This also applies to the recycling process, wherein the material used for paperclips must be separated from the paper. In addition, traditional paperclips have a single functionality, namely the binding of paper. Traditional paperclips do not have the possibility of combining promotional or illustrative expressions with the binding functionality. The final disadvantage of the traditional paperclips is that, when paperclips are applied to a larger quantity of paper sheets, the paperclip can spring off, whereby the clip itself may cause injury to the user (for example to the eye). Also a paperclip based on clamping force may damage the nails of the user when the clip is attached.
In the past, many improvements have been made to the traditional paperclip to increase the clamping force and prevent damage to the paper (for example U.S. D623.229 S, U.S. 2009/0165260 A1, U.S. 2009/0151129 A1). However the improved designs are usually based on the same connecting principle, namely by exerting a clamping force on the stack of sheets by the material used and by the shape of the paperclip. Hereby the disadvantage remains that sheets of paper can fall out from between the stack of papers joined together. Often alternative improved variants to the traditional paperclip can only be achieved at the cost of other functional requirements and properties in relation to the traditional paperclip, such as higher costs, less intuitive functionality, higher weight and more (non-sustainable) material use.
A second category of paperclips, promotional paperclips to which a promotional or illustrative expression can be applied, works on the same binding principle as traditional paperclips, namely by exerting clamping force on the stack of sheets (examples of this category of paperclips are GB930491, GB1561417, GB1582799, GB1602118). The advantage of this second category of paperclips is the possibility of combining the connecting function with the possibility of applying a promotional or illustrative expression to the paperclips by means of printing. The other disadvantages of the traditional paperclips persist with these paperclips.
A third category of paper binders uses connection by making a perforation through the stack of sheets and joining the sheets together by inserting a form/binder through the perforation (for example rivets, connecting clamps). The advantages of these paper binders is that they have a good binding quality and no sheets can fall out from the stack of joined papers. The disadvantages of this category of paper binders are that the material used (usually metal) is not sustainable, the paper is damaged by the perforation and the paper binders usually fulfill a single function. Also the removal of paper binders of this category is typically more complicated.
Next to the solutions mentioned above, there exists another solution for joining papers, namely by a paper corner device such as disclosed in NL1011526, in which a flat sheet is folded over the paper by folding movements, thus connecting the stack of sheets. The advantages of this paper binder are that the solution offers a good binding quality, no stacks of sheets can fall out from between the stack of papers, several functions can be combined (connecting and illustrative expression), there are no safety risks for the product and the paperclip is made of a sustainable material. Also thanks to the material used, the paperclip can be passed through a shredder and be recycled with old paper even without removing the clip from the stack of sheets. The disadvantage of this solution is the poor user-friendliness of the paperclip. The paperclip is attached by performing six actions (rotating clip, inserting paper, folding paper, folding part of clip, folding other part of clip, insertion of front of clip in recess to fasten the clip). Of these six actions, three are not intuitive. To remove the paperclip from the stack of sheets, all actions must be carried out in reverse order.
Another paperclip is disclosed in NL1011086. This document discloses a compact corner device for holding together a stack of sheets. The holding method of the corner device is characterised by a foldable lever arm with a recess therein, a rigid support which is created on the first folding action of the corner device, an open ridge between a rear surface in which a foldable clamping hook is integrated and a foldable front surface in which the closing corner is integrated. By using a punch form, the corner device can be attached to and removed from the stack of sheets in a number of actions.
One problem with existing solutions is that these are not user-friendly. The existing solutions require many actions from the user, of which a number of actions are not intuitive. The paperclip in NL1011086 is described as flat sheet. The attachment of the paperclip, like the paperclip in patent no. NL1011526, consists of six actions. First the paperclip must be rotated as the paper must be attached to the back side of the clip. Then a retaining arm must be attached behind a front surface by means of folding movement, by pushing this retaining arm into a small recess. Then the stack of sheets must be pushed between this retaining arm and the rear surface. The next step consists of folding the stack of sheets over the retaining arm. This takes place including a clamping corner which is integrated with the rear surface. The penultimate step is folding the front surface over 180° to the front. To attach the paperclip as a final step the closure must be pushed into a recess in the retaining arm. The paperclip is now attached and binds a stack of sheets. The disadvantage is that the paperclip needs six actions to attach it, that the fixing is not intuitive because the clip must be attached on the back side, and the fixing of the retaining arm takes place by partly deforming the retaining arm before this can be pushed into the recess in the rear surface.
Another disadvantage of this paperclip is that there is a protrusion on the side of the paperclip (visible from the front). This is the end of the retaining arm. Because of this protrusion, the paperclip with the stack of sheets cannot or not easily be placed in an envelope as the protrusion catches the back side of the envelope.